20385139104 has 180 divisors, whose sum is σ = 65898807282. Its totient is φ = 6177219840.

The previous prime is 20385139079. The next prime is 20385139109. The reversal of 20385139104 is 40193158302.

20385139104 is a `hidden beast` number, since 2 + 0 + 38 + 513 + 9 + 104 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19762736400 + 622402704 = 140580^2 + 24948^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20385139109) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 281134 + ... + 346130.

Almost surely, 2^20385139104 is an apocalyptic number.

20385139104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20385139104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32949403641).

20385139104 is an abundant number, since it is smaller than the sum of its proper divisors (45513668178).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20385139104 is a wasteful number, since it uses less digits than its factorization.

20385139104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65041 (or 65013 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 20385139104 in words is "twenty billion, three hundred eighty-five million, one hundred thirty-nine thousand, one hundred four".